The predominant structural components of the vitreous are collagenous fibrils. Prior biochemical analyses have been limited by incomplete solubilization of the constituent collagen types. The techniques described enable an effective separation and nearly complete solubilization of calf vitreous fibrils. Semiquantitative analysis has led to the detection of types II, V, and IX collagen in a ratio of 69:24:7, respectively. Qualitatively similar ratios were found in vitreous from other mammals, including rabbits, monkeys, and humans. Electron microscopic evidence suggests that type VI collagen may be distributed selectively near the vitreous base. These observations are pertinent to vitreous gel stabilization, aging, and disease.